Manufacture of window envelopes



1940- F. L. SMITHE ET AL MANUFACTURE 0F WINDOW ENVELOPES Original Filed July 13, 1934 6 Shee s-Sheet l m mmw m M w L, m/ MM ma m Feb. 27, 1940. $M|THE AL 2,191,505

MANUFACTURE OF WINDOW ENVELOPES Original Filed July 13, 1934 6 Sheets-Sheet 2 and Abra/2am Nor/ck A TTORNEYS.

Feb. 27, 1940. 5W5 ET 2,191,505.

MANUFACTURE OF WINDOW ENVELOPES Original Filed July 13, 1934 6 Sheets-Sheet 3 INVE 0R5 Ferd/hand H m/r/{e ATTORNEYS Feb. 27, 9 0- F. 1.. SMITHE ET AL MANUFACTURE OF WINDOW ENVELOPES 6 Sheets-Sheet 4 Original Filed July 13, 1934 INVENTORS 80 Ferd/Hand L. Sm/Ine BY giiiaham Nor/ck.

ATTORNEYS.

Feb. 27, 1940. F. L. SMITHE ET AL IIANUFACTURE 0F WINDOW ENVELOPES Original Filed July 13, 1934 6 Sheets-Sheet 6 Y INVENTORS Fem/"and L. Sm/fhe Y and Abraham Nor/ck.

A TTQRNEYS.

v Patented Feb. 27, 19 40 UNITED STATES PATENT OFFICE MANUFACTURE OF WINDOW ENVELOPES Ferdinand L. Smithe, New York, and Abraham Novick, Flushing, N.

Y., asslgnors to F. L.

Smithe Machine 00., Inc., New York, N. Y., a corporation of New York Application July 13, 1934, Serial No. 734,978 Renewed October 6, 1938 14 Claims.

This invention relates to the manufacture of window envelopes and is in the nature of an improvement upon the invention disclosed in Letters Patent of the United States #l,827,539, granted to Abraham Novick on October 13, 1931.

In common with the procedure followed in the invention of said patent, provision is made for operating on envelopes having window openings cut in the bodies thereof. The securing flaps of the blanks are first gummed. and the blanks in fanned-out condition are carried by a drying con veyor to the subsequent operating instrumentalities. Such instrumentalities comprise means for realigning the blanks in spaced out condition as they are delivered by the drying conveyor, means for applying gum to the window margins and securing window patches to the blanks, and means for thereafter adhesively uniting the side and bottom flaps of the blanks.

It is an inportant object of the present invention to provide for the transferring and spacing out of the blanks as they leave the drying conveyor in such manner that all liability of a window edge of one blank catching a window edge of an adjacent blank is avoided. To this end it is a feature that the blanks delivered by the dry.- ing conveyor in one path are projected across a gap so that they may bend down under the influence of gravity and that the next subsequent blank feeding means is located in a lower plane than the path of delivery of theblanks. Provision is made in the plane of said second feeding mechanism of means for intercepting the leading edges of the blanks and limiting bending of the blanks. The arrangement is such that the window area of each blank bridges across the gap out of contact with the window areas of adjacent blanks, so that when rapid advance of the leading blank takes place, the blank is free to advance Without obstruction.

Other objects and advantages will hereinafter appear.

In the drawings forming part of this specification:

Fig. l is a fragmentary view in side elevation, largely diagrammatic, illustrating a portion of the drying conveyor and of the feeding-and aligning mechanism to which the blanks are delivered by the drying conveyor; v

Fig. 2 is a view in sectional elevation illustrating an end portion of the drying conveyor and a series of instrumentalities for acting on the blank afterit has left the drying conveyor;

Fig. 3 is a plan view of a bed cylinder which supports the blank during application of a patch thereto; 1

Fig. 4 is a fragmentary plan view of the mechanism of Fig. 2;

Fig. 5 is a fragmentary diagrammatic view in side elevation on a larger scale than the preceeding figures, illustrating the transfer of the blanks from the drying conveyor to the blank spacing and feeding mechanism;

Fig. 6 is a fragmentary detail view partly broken away illustrating the patch feeding, cutting and applying mechanism;

Fig. 7 is a sectional view illustrating the patch transferring and applying segment at a different point in the cycle from that illustrated in Fig. 6;

Fig. 8 is a view in sectional elevation illustrating mechanism for variably driving the patch transferring and applying segment;

Fig. 9 is a view in sectional side elevation, partly broken away and largely diagrammatic, illustrating a modified form of machine, and

Fig. 10 is a plan view of an envelope blank as supplied to the machine of Fig. 9.

The envelope blanks I each comprising a sealing flap 2, a bottom flap 3, side flaps 4 and a body portion having a window opening 5 provided therein, are supplied to the machine and gummed along the margins of the sealing flaps in any suitable manner, for example, in the manner illustrated in my patent referred to above. The blanks are then delivered in overlapped or fanned-out relation to a drying conveyor 6, to which they are clipped. The drying conveyor runs around a cylinder 1 and carries the blanks onto an extensible table 8 comprising relatively adjustable sections Sand Ill. The conveyor 6 comprises chains l l which run at the delivery end of the conveyor upon sprockets l2 which are fast upon a shaft I3. The shaft l3 also has fast upon it a feed roller M which cooperates with a lower feed roller l5 for delivering the blanks away from the conveyor. adjusting the shaft l3 and the roller l5 longitudinally of the table 8, and for appropriately readjusting the chains l I. The table 8 desirably extends substantially horizontally and is adjusted to terminate in. line with the line of contact of the rollers I 4 and I5. The blanks are delivered,

Provision is made for the blanks which border upon the window openings are shown cross-hatched for the purpose of blanks are unsupported for a space after they leave the feed rolls l4 and I5 and they therefore bend downward under the force of gravity until their leading edges are intercepted and supported by a table 16 which is located in a lower plane than the table 8 and which desirably extends substantially parallel to the table 8. The upper surface of the table l6 stands substantially tangent to a pair of feed rollers I1 which are fast upon a shaft l8. The shaft l8 also has fast upon it a pair of sprockets l9 upon which parallel chains 20 run at the same linear speed as the peripheral speed of the rollers l1. The upper stretches of the chains 20 travel in the plane of the top of the table '16 and the chains are provided with transversely aligned pins 2| which travel in unison and which are adapted to engage in the angles of the blank formed at the junctions of the sealing flap with the side flaps. Sectors 22, fast upon a shaft 23, are driven in unison with the rollers 11 and the conveyor.

chains 20.

As seen in Fig. 5 the leading blank I is in a position in which it is gripped between the rollers I1 and the sectors 22 to be fed rapidly forward. In this action it should be observed that the sectors 22 and the rollers I1 engage the blank outside the lateral bounds of the window area so that they do not act upon the forward extremity of the blank at the middle of the bottom flap. The blank l is also nearly ready to leave the bight of the rollers I4 and [5. The forward end of the blank bridges the space between the roller 15 and the table l6 and stands out of contact with the blank l When the sector reaches blank-engaging position the blank I is in position to be gripped and advanced rapidly by the sector and the sector then advances the blank rapidly to locate the trailing edge of the blank in position to be engaged and pushed forward by a pair of pins 2i. The sectors again become ineffective, however, before the leading edge portions of the blank I which can be engaged by the sectors 22 have been advanced far enough to be engaged by the sectors. It will be observed that during the movement of the blank l relative to the blank l because of the bridging action, the blank is entirely out of contact with the blank l in the overlapping window areas of the blanks, so that there is no danger of the trailing edge of the window of blank i catching upon the leading edge of the window area of blank l It is to be noted that the bite of the roll I4 is suitably regulated to effect the necessary feeding action without exerting such a drag upon the trailing end thereof as to cause rupture of the blank when the sectors 22 enter into engagement with the leading edges at the side of the blank (see Fig. 4)

Sometimes a tongue 23 may be used to assist in bending the blank I away from the blank l said tongue extending down through the window opening 5 of the blank l to the blank beneath. The tongue 23a is especially advantageous when the blanks are composed of heavier weight material or when the material has a reverse curl. The tongue 23a is sufficiently resilient to lift out of the window opening while the upper blank is being fed from the position in Fig. 5.

After the rollers l1 and the sectors 22 have acted to pull the leading blank substantially clear of the pack the blank is overtaken by the pair of pins 2| and advanced in definitely timed and aligned condition to subsequent operating instrumentalitles. The chains 20 travel at their discharge ends upon sprockets 24 and the table l6 terminates a little beyond these sprockets. A feed roller 25 and cooperating feed segments 26 which travel a little faster than the chains 20 act to pull the blanks away from the pins 2| and to feed them between opposed lower and upper conveyors 21 and 28. The conveyor 21 comprises a pair of laterally spaced belts 29 and the conveyor 28 comprises a pair of similarly spaced, opposed belts 30. The belts 29 run upon end rollers 3| and 32, upon a roller table between the end rollers consisting of a series of rollers 33, supported on stub shafts 33 and upon idler rollers 34 and 35. The belts 30 run upon end rollers 36 and 31 and upon idler rollers 38 and 39. The rollers 33 of the roller table are supported on suitable plates, not shown, at their outer ends,

' and they are arranged with their axes disposed upon an arc of slight curvature so that the upper stretches of the belts 29 are slightly convex. This convexity of the lower belt contributes substantially to the secure gripping of the blanks between the belts since it causes the belts 30 to exert positive pressure against the belts 29 at all points between the end rollers 36 and 31.

The conveyors 21 and 28 carry the blanks in definitely timed relation past a gumming segment 40 which travels at a peripheral speed equal to the linear speed of the conveyors 21 and 29. Gum is applied to the segment 40 from a gum pot M by means of a gum take-up roller 42 which runs in the pot 4| and a gum transfer roller 43 which stands in contact with the roller 42 and tangent to the path of the gumming segment 40. The gumming segment 40 operates between the belts 30 to apply gum to the margins of the blank which border upon the window opening. Opposite the gumming segment 40 provision is made of a bed cylinder 44 which runs in a water receptacle 45. When a gap occurs in the normal sequence of blank delivery gum applied to the bed cylinder 44 is carried into the water in the receptacle 45. A submerged scraper or brush 46 assists in wiping the gum from the face of the bed cylinder 44 and a further scraper 41 wipes the water from the bed cylinder as the cylinder emerges from the receptacle.

The gummed blank is also advanced by the conveyors 21 and 28 past a patch applying mechanism. This mechanism comprises a supply reel 49 from which a web 50 of transparent patch material is drawn by continuously operating feed rollers 5i and 52. The patch material is fed onto a table 53, the forward edge of which is provided with a shearing block 54 forming one element of a patch severing device. A blade 55 is adapted to co-act with the block 54 being carried by a rocking frame 56 which is normally held up by a spring 51 connected to an ear 58 of the rocking frame and to a fixed frame member (not shown). The rocking frame is provided with a roller 59 which serves as a cam follower for engaging the periphery of a rotating cam 60. The cam 60 is vofgenerally circular contour but is provided with normally to co-act with the roller 5|. The disc 65 may be turned by means of a handle 65 to raise the tail 84 to lift the roller 52 out of engagement with the roller 5| to facilitate the insertion of a fresh patch web. A spring 68 connected to an arm 69 of the frame 62 and to a fixed part of the machine frame acts to urge the frame 62 counter-clockwise and hence to urge the roller 52 toward the roller 5|.

The leading end of theweb which protrudes beyond the cutting block .54 extends into the path of a patch transferring and applying segment 10 which travels about a hollow shaft II and cooperates with a bed cylinder 10*. The segment 18 travels into supporting relation to the web end lifting it to the position illustrated in Fig. 7, where the patch web 50 is sucked against it while it is slack. The segment 10 then travels further dragging over the surface of the web to the position in Fig. 6 where the web is taut. In the position of Fig. 6 the cutting device is about to operate. At the instant of patch severance the leading edge of the web stands between the leading edge of the cylindrical surface of the segment 18 and a row of suction passages I2 provided in the segment near the leading edge thereof. The segment 10 carries the severed patch around and co-acts with the bed cylinder 10 to press the patch in proper position against the gummed envelope blank.

The segment 10 is carried by a rocker arm 14 which is mounted upon a shaft 15 journalled in a crank 15 fast on the shaft II. A tail portion 11 of the rocker arm H is drown toward the axis of the shaft H by a spring "connected to such tail portion and to a pin 19 which travels with the shaft. The tendency of the spring 18 is to project the segment 10 outward away from the axis of the shaft H. The outward limit of movement of the segment is controlled by an adjusting screw 80 which is threaded through the tail portion 11 and. which engages a hub 84 of the crank 16. A lock nut 82 is provided for maintaining the screw 80 in adjusted position. With this arrangement the segment 10 is adapted to yield when it engages the envelope blank and hence to apply the patch with light but firm and substantially uniform pressure to the blank. The arrangement disclosed does not ordinarily require resetting for operating upon blanks of different thickness nor is it affected by any moderate amount of wear.

The suction is applied to the passages 12 through passages 83 and 84 formed in the segment 10 and the rocker arm 74. The passage 84 communicates through a nipple 85 with a flexible tube 86. The tube 86 in turn communicates through a nipple 81 with a radial passage 88 of the shaft H. The passage 88 communicates through the axial passage 89 of the shaft H with a suitable source of suction. The flexible tube 86 turns with the shaft H and is adapted to yield to accommodate such movements of the segment 16 relative to the shaft H as occur in the normal operation of the machine and lso such movements as may be produced by adjustment of the screw 80.

After the patch is applied to .a blank the blank is delivered by the conveyors 21 and 28 toa subsequent conveyor 99 whereby it is delivered to the other instrumentalities for completing the manufacture of the blank into a finished envelope.

In Fig. 8 disclosure is made of mechanism for driving at variable speed the shaft ll whereby the segment 10 is carried. The driving means is so constructed and arranged that the segment is caused to come to rest substantially simultaneously with the severing of a patch, and to be thereafter smoothly accelerated to the speed of the envelope blanks so that the segment travels in unison with a blank when applying a patch to it.

A gear 9| is secured to a shaft 9| and rotates at uniform speed, to drive a gear 92, which is journalled on the shaft II, at uniform speed. The gear 92 has fast upon it a block 93 to which a link 94 is pivotally connected. The link 94 forms one member of a toggle or knuckle, the other member of the toggle or knuckle being a link 95. Both of the links 94, 95 are pivotally connected to a pin 96 which carries a cam followingroller 91. The end of the link 95, remote from the pin 96 is pivotally connected, by means of a pin 98, to a crank 98 which extends outward from a collar 99, the collar being made fast to the shaft H by means of a pin I08. The roller 91 runs in a cam track lill provided in a cam I02. The cam N12 is mounted upon a stationary plate I03, being adjustable relative to the plate about the axis of the shaft 1|. Marginal portionsof the plate I63 are provided with arcuate slots )4 concentric with the shaft H, and the cam is clamped in place by means of bolts nuts Hi6.

If the cam block IOI were circular and concentric with the shaft H, the gear 92 and the shaft H would obviously rotate in unison at all times. The cam, however, is so designed that the uniform rotation of the gear causes the shaft H to come to rest for a brief period just as the patch is severed and then to be accelerated to the speed of the envelope blanks. This result is very readily and simply achieved by making a portion of the cam track, bounded by the lines 95 and 95 concentric with a point in the circular pathof the axis of the pin 98 When the roller reaches the portion of the cam track referred to, it is incapable of moving otherwise than about the center of the pin 98, and hence during this interval the link 95 has only pivotal movement and no bodily or translational movement. The center of the pin 98 is therefore held stationary with the result that the crank 98, the shaft II, and the segment 70 are held stationary.

In the ultimate result, the patch segment is driven substantially the same as the patch transferrer disclosed and claimed in Letters Patent of the United States, No. 1,831,575 granted to Abraham Novick on November 10, 1931. Structurally, however, the mechanism of the present application is simpler. The patch segment of the present application, moreover, applies the patch directly to an envelope blank, there being no intermediate transfer of the patch to a separate applying member.

The cam is made adjustable in order to cause the period of rest to occur at the point in the revolution of the segment 10 appropriate to the length of patchemployed. When long patches are used, the segment should come to rest a little later in the cycle than when short patches are used, so that the leading edge of the patch will always be located a little in advance of the suction passages 72 at the moment of severance. Different lengths of patches are provided by changing gearing in the driving train of the patch web feeding roller 5|.

It is, of course, intended that an envelope blank will always be present and ready to receive a patch at the time that the patch applying segl05 and clamping ment comes opposite the bed cylinder-10 It occasionally happens, however, that a gap occurs in the series of blanks. stances, it is not desirable to permit the unused patch to get into the machinery. Provision is accordingly made in the bed cylinder 10 of a series of suction passages II" for securing the patch to the bed cylinder when no blank is present. These suction passages are so located in the bed cylinder that they normally, engage a margin of the envelope blank bordering upon the window opening so that the suction is not applied to the patch at all when the blank is present. The suction passages, therefore, have no tendency to disarra-nge the patch with reference to the blank in normal operation. When the suction passages do take control of the patch, however, in the absence of a blank, the bed cylinder III carries the patch around with it until it is intercepted and caused to be stripped ofi by suitable fingers I08 which lie in circumferential grooves I09 formed in the periphery of the bed cylinder 10 The unused patch is thus disposed of in an orderly manner.

.At times there is a tendency for the envelope blank to adhere to the cylinder 10 and follow it around. To avoid this there is provided a stripper III] which is normally away from the cylinder and is supported by an arm II Ii on a shaft IIIl Just before the leading edge reaches the stripper the latter is moved against the cylinder to deflect the blank therefrom and the stripper then returns to its normal position (Fig. 2). This occurs before the window patch reaches the stripper so that the patch may pass around the cylinder to be thrown out in the absence of an envelope blank.

In Fig. 9 disclosure is made of a modified form of window envelope machine which is adapted to deal with whole blanks which are either supplied to the machine with the sealing flaps already gummed, or which are intended to be manufactured into second class envelopes. Many of the elements of this machine are duplicates of elements Figs. 1-8. As to such elements the same reference numerals have been applied with the superscript It added and these elements will not be described in detail.

In the machine of Fig. 9, whole blanks III] are supplied from a stack I I I which is supported by a magazine II2. The blanks are taken from the stack by a mechanism like that disclosed in Figs. 10-16 inclusive of the pending application of Abraham Novick, Serial No. 628,302, filed August 11, 1932, for Envelope machines. Such mechanism comprises a supporting or detaining plate H3, a suction picker II4, a separator II5, a cylinder H6, and oscillatory auxiliary rollers H8. The suction picker moves into engagement with the exposed margin of the bottom-most blank and then away from the stack to draw the edge of the bottom-most blank past the supporting or detaining finger II3. While the picker II4 holds a margin of the lower-most blank thus separated from the stack, a pair of dagger members is moved forward into the space between the stack and the partially separated blank to move the edge of the partially separated blank into proximity to the cylinder IIB. After the separator members have entered the spaces between the stack and the margin of the bottom blank, the suction picker H4 is withdrawn longitudinally of the plane of the blank to permit the blank to clear it. The dagger members of the separator II5 press the margin of 'the blank close to but Under such circumnot into gripped relation with cylinder H6. The auxiliary rollers II8, which run constantly in engagement with the cylinder IIB, are moved counter-clockwise about the axis of the roller II6 into position to grip the leading margin 01. the blank. The blank is advanced by the cylinder III; in cooperation with roller II9 onto a table I20, being taken up, aligned and advanced by a conveyor 20 and delivered to conveyors 21" and 28. As the blank is advanced by the latter conveyor, it is fed first past-a window cutting die I2I which coacts with a bed cylinder I22. The bed cylinder is provided with pins I23 which penetrate the window chip and carry it around to be discharged by a stripper member I24. From this point the parts disclosed are all duplicates of the parts disclosed in Figs. 1 to 8, and no further detailed description is therefore deemed necessary.

The mechanism disclosed herein, and in the pending application of Abraham Novick, Serial No. 738,095 (now Patent No. 2,125,308) for feeding a patch to a blank and applying the patch to the blank is not claimed herein, but is claimed in our divisional application, Serial No. 18,402, filed April 26, 1935, for Manufacture of window envelopes.

We have described what we believe to be the best embodiments of our invention. We do not wish, however, to be confined to the embodiments shown, but what we desire to cover by Letters Patent is set forth in the appended claims.

We claim:

1. In a machine for making window envelopes, in combination, means for delivering window blanks in a fanned outpack with the overlapping bodies of the leading blanks free from contact with each other in the window areas, and means for engaging the leading margin of the foremost blank in advance of the leading margin of the second blank and pulling the foremost blank clear of the pack.

2. In a machine for making window envelopes, in combination, means for delivering fanned out window blanks divergently so that the window areas of adjacent blanks are out of contact, and means for advancing the foremost blanks clear of the others.

3. In a machine for making window envelopes, in combination, means for delivering fanned out window blanks with the leading portions thereof unsupported, means standing in intersecting relation to the direction of delivery of the blanks to deflect the blanks successively and progressively, to space the window areas of the leading blanks from one another, and means for advanc- Ing the leading blank relative to the others.

4. In a machine for making window envelopes, in combination, means for delivering fanned out window blanks with the leading ends thereof unsupported so that they droop under the influence of gravity, means for intercepting and deflecting the leading edges of the blanks successively to separate the window area of the leading blank from the window area of the next-blank, and means for advancing the leading blank relative to the others. i

5. In a machine for making window envelope in combination, means for delivering window blanks with each blank protruding at the leading margin thereof beyond the leading edge of thenext underlying blank, and means extending in intersecting relation to the direction of movement of the delivered blanks to deflect and lift the following blank.

6. ma machine formaking window envelopes,

' in combination, means for feeding window blanks in fanned out relation, said feeding means. terminating abruptly and discharging the blanks with the leading ends unsupported, and a table extending across the direction of delivery of the blanks to receive the leading edges of the blanks seriatim as each such edge becomes unsupported, and to cause each blank as its edge engages and moves along the table to bridge the space between the feeding means and the point of contact with said table, in such fashion that the windowed portion of each blank is self-sustained out of contact with the underlying body of the follow-,

ing blank.

7. In a window envelope machine, in combination, means for delivering window blanks with each blank, protruding at tire leading margin thereof beyond the leading edge of the next un-' derlying blank, means extending in intersecting relation to the direction of movement of the delivered blanks to deflect and lift the windowed portion of each blank away from the following blank, and complemental deflecting means to depress each blank away from the overlying preceding blank.

8. In a window envelope machine, in combination, means for delivering window blanks with each blank protruding at the leading margin thereof beyond the leading edge of the next underlying blank, and means extending in intersecting relation to the direction of. movement of the delivered blanks to deflect and'depress each blank away from the windowed portion of the preceding blank.

9. In a window envelope machine, in combination, means for delivering window blanks with each blank protruding at the leading margin thereof beyond the leading edge of the next underlying blank, and means extending in intersecting relation to the direction of movement of the delivered blanks to deflect each blank away from the windowed portion of the adjacent blank.

10. A mechanism for advancing windowed envelope blanks seriatim from contiguous fannedout positions, said mechanism comprising the elements combined and cooperating as set forth in claim 9, and further characterized by having said deflecting means formed as a flnger disposed in position to traverse the window opening of an overlying blank into depressive engagement 11 Ina machine for makings vindow envelopes, a roll couple for feeding window blanks in fanned out. relation, said roll couple discharging the blanks with the leading ends unsupported, a second roll couple having its bite disposed at a lower level than that of said first-named couple, and a table between said roll couples, and along which the leading edges of the blanks are directed successively toward the bite of said lastnamed couple as said leading ends are inclined downward by gravity into contact with the table, the windowed portions of adjacent blanks being out of contact.

12. In an envelope blank patching machine, a run of mechanism comprising a pair of endless chain conveyors spaced apart, and respectively having means to align and feed an envelope blank, and an intermediate conveyor in the space between-said chain conveyors and adapted to exert exclusively frictional action to carry said blank from chain to chain across said space,

whereby said blank will be aligned by the first chain, may be gripped without rupture during transfer by saidintermediate conveyor, and will be re-aligned by the second chain conveyor.

13. The method of individualizing fanned out window envelope blanks, which comprises supporting the blanks in the form of a fanned out band, progressivelyadvancingthe band to deliver the blanks at the leading end of the band into an unsupported condition so that the blanks are caused to bend individually under the influence of gravity to separate the window areas of contiguous blanks at the leading end of the band from one-another, and pulling the bent blanks with an accelerated movementindividually from the band, each as it becomes the leading blank of the band. v

14. In a sheet feeding conveyor, in combination, spaced apart driving and driven pulleys. a driven conveyor belt passing over said pulleys, at least three small rollers disposed between said pulleys and also between the active and inactive stretches of the belt and in contact with the actice stretch thereof, the axes of said rollers being disposed on an arc oflarge radius whereby the active stretch of the belt is supported with its sheet engaging surface in a convex curve of large radius, an opposed sheet gripping belt, and a pair of end rollers supporting said last named belt out of contactv with said small rollers and with one of its surfaces in juxtaposed relation to the convexly curved sheet engaging surface of said driven belt.

' FERDINAND L. SMITEI.

NOVIC'K. 

